1. Field of the Invention
The present invention relates to a light output member, a light emitting device assembly including the light output member, a surface light source device including the light emitting device assembly, and a liquid crystal display device assembly including the surface light source device.
2. Background Art
As a liquid crystal display device assembly, a liquid crystal display device assembly including a liquid crystal device in which a liquid crystal material is sandwiched between two panels opposed by superimposing transparent glass substrates with transparent electrodes, alignment films, etc. stacked thereon, and a surface light source device provided under the liquid crystal display device (in the Z-axis direction) for supplying illumination light to the liquid crystal display device is known. Further, as the surface light source device, a direct-type surface light source device is known.
As shown in a conceptual diagram of FIG. 25A, a direct-type surface light source device 870 includes a light source 820 provided within a casing 871, a reflector member 885 that reflects output light from the light source 820 upward, and a light diffuser plate 881 that is disposed to an opening of the casing located above the light source 820 and diffuses the output light from the light source 820 and the reflected light from the reflector member 885 through itself. Further, the light source 820 includes plural red light emitting diodes, plural green light emitting diodes and plural blue light emitting diodes, and white light with high color purity obtained by mixing red, green and blue light output from these light emitting diodes is used as illumination light.
In a configuration in which light output from light emitting diodes is entered directly into the liquid crystal display device located above, that is, when light is output from the light emitting diodes mainly in the Z-axis direction, luminance irregularities and color irregularities occur in the surface light source device. Accordingly, a two-dimensional-direction output configuration using a light emitting diode assembly including a luminous flux control member having a recessed part on the upper surface and light emitting diodes as a light source for outputting the light output from the light emitting diodes from the luminous flux control member in a horizontal direction is known from JP-A-2006-092983, for example. Further, a structure using a light emitting diode assembly including a lens having a characteristic shape and light emitting diodes as a light source for outputting the light output from the light emitting diodes from the lens in a predetermined direction is known from JP-A-2007-188858, for example.